Paper bag with integral locking tabs



Feb. 23, 1960 J, DAWS 2,925,951

PAPER BAG WITH INTEGRAL LOCKING TABS Filed May 21, 1957 INVENTOR.

AT TOR Y5 United States Patent 2,925,951 PAPER BAG WITH INTEGRAL LOCKING TABS John Davis, Scarborough, N.Y., assignor to Equitable Paper Bag Co. Inc., Long Island City, N.Y., a corporation of New York Application May 21, 1957, Serial No. 660,553

3 Claims. (21. 229-77 This invention relates to improvements in paper bags, and more especially to a construction having tabs which can be inserted into slits in the bag panels for locking the bag closed.

It is an object of this invention to provide improved and more convenient means for locking paper bags closed. Another object is to provide a paper bag construction with tabs displaced from panels of the bag and constructed so that they can be folded back into positions to hold a bag flap closed.

In accordance with one feature of the invention, the tabs are made with side edges which converge toward the hinged end of the tab so that the tabs perform a locking function without being folded back and tucked through slits in the bag panels. In accordance with another feature of the invention, slits are provided with lengths greater than the widths of the tabs for quick and convenient insertion of the tabs through the panels of the bag.

In the preferred construction, two groups of locking tabs are provided, and these groups are displaced from areas which are large enough to receive the fingers of a person carrying the bag, and at convenient spacing for holding with the first two fingers of the hand.

Other objects, features and advantages of the invention will appear or be pointed out as the description proceeds,

In the drawing, forming a part hereof, in which like reference characters indicate corresponding parts in all the views:

Figure 1 is a back view of a paper bag made in accordance with this invention;

Figure 2 is a front view of the bag shown in Figure 1;

Figures 3-9 are diagrams showing the way in which the tabs are inserted into the slits of the bag;

Figure is a greatly enlarged sectional view taken on the line 10-10 of Figure 1;

Figure 11 is a greatly enlarged sectional view taken on the line 1111 of Figure l but with the tabs extending rearwardly before insertion into the slits in the panels;

Figure l2 is a greatly enlarged sectional view taken on the line 12-12 of Figure 1 but with the edges of the slits displaced for initial insertion of the tabs into the group of slits; and

Figure 13 is a view similar to Figure 2, but showing a modified form of the invention.

Figure 1 shows a paper bag having a front panel 21, a back panel 22, and a flap panel 23. The flap panel 23 can be folded down between the front and back panels 21 and 22, respectively, but it is preferably folded across the top of the bag 20 and downwardly along the outside of the back panel 22, as shown in Figure l.

A group of tabs 25 are displaced from the panels leaving an opening 27 through all of the panels. Other tabs 29 are similarly displaced from the panels, at another location, leaving an opening 30. In the preferred construction, the openings 27 and 30 are large enough to receive the fingers of a hand by which the bag is carried, and they are preferably spaced from one another with a center distance of approximately one to two inches for comfortably receiving the first two fingers of the hand, as previously explained.

The tabs 25 remain connected with the panels, from.

which they are displaced, along a hinge line indicated by the reference character 32. The tabs 25 are folded back along this hinge line 32 and into contact with the outside surface of the flap panel 23. The ends of the tabs 25 are inserted through a slit opening 34 which extends through all of the bag panels.

By constructing the tabs 25 so that the sides of the tabs converge toward the hinge line 32, the tabs 25 will function to hold the bag closed even though the tabs are not inserted into the slit opening 34. V

This feature is clearly illustrated in Figure 11 where the tabs 25 are shown extending in directions substantially normal to the planes of the panels 21, 22 and 23.

The flap panel 23 can not be moved away from the back panel 22 while the tabs 25 are in the positions shown in Figure 11 except by bending the tabs 25. Since there are three tabs in this group of tabs 25, they oifer a substantial resistance to bending.

Referring again to Figure l, the slit opening 34, which extends generally parallel to the hinge line 32, is spaced from the hinge line by a distance somewhat less than the length of the tabs 25 and preferably by a distance between two-thirds and three-quarters of the length of the tab. In accordance with one feature of the invention, the slit opening 34 is substantially longer than the width of the portion of the tabs 25 that extend into the slit opening. This provides suflicient clearance for snapping the ends of the tabs into the slit opening in a manner which will be more fully explained in connection with Figures 3-8. i

In Figure 3 the tabs 25 are shown in the positions in which they are first displaced from the opening 27 through the panels 21, 22 and 23.

Figure 4 shows the tabs 25 bent outwardly along the hinge line 32 and into a position substantially normal to the surface of the bag.

Figure 5 shows the tabs 25 folded back across the back surface of the bag and illustrates the way in which the tabs 25 extend beyond the slit opening 34.

Figure 6 shows the tabs 25 pressed against the surface of the bag so as to open up the slit opening 34; and in Figure 7 pressure is applied in opposite directions, as indicated by the arrows, against the front and back of the bag on difierent sides of the slit opening 34 so as to permit the bent-back ends of the tabs 25 to snap past one edge of the slit opening 34. The bent-back ends of the tabs 25 straighten out when they snap past the obstruction provided by the edge of the slit opening 34, and when the distorting pressures are removed from the bag surfaces, the ends of the tabs 25 remain inserted through the slit opening 34, as shown in Figure 8.

Figure 9 shows another way in which the tabs 25 can be inserted through the slit opening 34. In this figure, the tabs 25 are arched, as shown, so as to bring the ends of the tabs back to the slit opening 34. By only a small distortion of the bag on opposite sides of the slit opening 34, sufiicient clearance can be provided for insertion of the tabs 25 through the slit opening 34.

Figure 10 shows a greatly enlarged sectional view through the panels of the bag and through the tabs 25 when the tabs are in their final positions inserted through the slit opening 34. In order to obtain sections thick enough for section lining and clear illustration, it has been necessary to greatly exaggerate the thickness of the panels and tabs in Figure 10.

Figure 12 shows the edges of the slit opening 34 displaced in opposite directions to provide a clearance for passage of the front ends of the tabs 25 into the slit Patented Feb. 23, 1960 opening 34. It will be understood that the stifiness of the paper, from which the bag is made, causes the panels to flatten out as much as they can after the tabs 25 have been put through the slit opening 34, and this holds the tabs 25 against displacement unless suificient force is applied to bend the tabs; such bendingbeing necessary to pull them out of the slit opening 34'.

Figure 13 shows -a modified form of the invention in which a group of tabs 25 are displaced from an opening 27 extending through all of the panels of a bag 40. These tabs 25' are hinged to the panels of the bag along a hinge line 32 which extends generally parallel to the top edge of the bag instead of being at right angles to it as is the case of the hinge line 32 in Figure l. The tabs 25 are tucked into a slit opening 34' which extends through all of the panels in the same manner as described in the other figures.

The construction shown in Figure 13 requires a longer fiap panel than is necessary with the construction shown in Figure 1, and it is more difficult to insert the tabs 25' into the slit opening 34' than it is to insert the tabs 25, of Figure 1, into their slit opening 34, when the slit opening 34' is near the top of the bag. This difference results principally from the smaller area available for gripping the bag above the slit opening 34.

It will be understood, however, from Figure 13, that the locking tabs can be constructed to extend in any direction, though the preferred construction is'that shown in Figure l where the hinge lines, along which the different groups of tabs are folded, are located at opposite ends of the openings 27 and 30 so that the groups of tabs 25 and 29, respectively, fold in opposite directions and away from one another when being moved into locking position.

This invention provides a locking device which can be used with light basis weight paper. It issuitable for use with the lightest paper which is practical for bag construction, and on any bag it provides a very secure lock, but one that can be opened easily when desired by merely pulling the tabs 25 and 29 away from the bag so that they bend and pull clear of the slit openings 34, after which the tabs 25 and 29 are folded back into the openings 27 and 30 respectively, from which they were displaced.

The construction has the additional advantage that the kind of die station necessary for making the bag can be installed on almost any standard bag-making machine. The tabs are such that they can be cut by rotary dies after the bag has been cut out.

Having the different tabs 25 of the same size and displaced from overlying areas, so that they are in substantial register, makes it possible to manipulate all of the tabs of the group as a unit. The tabs 25, and the corresponding tabs 29 and 25, can be displaced toward either the front or the back of the bag and inserted through the slit-openings with equal facility regardless of whether displaced forwardly or rearwardly.

The preferred embodiments of the invention have been illustrated and described, but changes and modifications can be made and some features can be used in different combinations without departing from the invention as defined in the claims.

What is claimed is:

1. A paper bag having front and back panels and a flap panel formed by an extension of the material of the front panel in the direction of the length of the bag beyond a fold line at which the flap panel joins the front panel and along which the flap panel is folded across the open end of the bag and across the upper end of the bag panel and down over the outsidesurface of the bag panel to close the bag, a group of three tabs displaced from aligned openings of the panels but connected to their respective panels along hinge lines, and all extending in the same direction through said aligned openings and all folded back in the same direction across the same outside surface of the bag, said group including one tab from each of the front, back and flap panels, said front, back and folded flap panels having a group of aligned slits therethrough extending parallel to the hinge lines and spaced a substantial distance from the hinge lines of the tabs and from the fold line of the flap and through which end portions of all three of the tabs extend in a different direction than the; tabs extend through the aligned openings inthe panels to' hold the three tabs together as a unit and folded substantially flat-against said outside surface whereby the flap panel is held in its folded position and the bag held closed by said flap.

2. The paper 'bag construction described in claim 1 and in which there are two groups of tabs and both groups have their hinge connections to the panels extending lengthwise of the bag whereby folding and unfolding movements of the tabs are in a different plane from that in which the panels must move to open the bag, and in which there is a different group ofslits for each group of tabs and the slits of each group are located on a different side ofits tabs from the slits of the other group whereby the different groups of tabs are differently affected by stresses tending to' open the'bag.

3. The paper bag construction described in claim 1 and in which the openings from which the tabs are displaced are generally circular except for converging portions near the hinge ends of the tabs, and the group of slits is spaced from the hinge connections of the tabs of the panels by a distance equal to approximately twothirds to three-quarters of the length of the tabs to facilitate snapping of the tabs past the far edges of the slits when the tabs are inserted into the slits by displacing the tabs and the edge portions ofthe slits on the tab-hinge sides of the slits rearwardly with respect to the other edges of the slits.

Rosenfeld Dec. 10, 1935 Poppe Apr. 29, 1941 

